File checksum checker
Check a file’s fingerprint and compare it with a trusted SHA-256 value.
- 1Choose a file
- 2Calculate SHA-256
- 3Compare & save
Local processing. No file upload.
0 bytes checked
Choose a file to calculate its SHA-256 fingerprint, or try the example.
Your file fingerprint
Select the value to copy it manually, or save a .sha256 file alongside your original.
Processed on your device. No file upload.
How to use File checksum checker
- Choose a file or try the known abc example.
- Optionally paste an expected SHA-256 value, then calculate.
- Review the match, copy the checksum or download the .sha256 file.
Check a received file against the original
A SHA-256 checksum summarizes the exact bytes of a file. Ask the sender for their checksum through a trusted channel, then choose your received copy and paste the expected value. Names do not affect the checksum; editing, converting or recompressing a file does.
Try a reproducible example
Use the abc example to hash a three-byte text file with no newline. Its SHA-256 begins ba7816bf and ends f20015ad. The example fills in the complete known checksum so you can check the match and download a standard .sha256 record.
What a match can tell you
A matching value is evidence that the file bytes agree with the expected checksum. It does not identify the sender, prove authenticity or scan for malware. If an untrusted source can replace both the file and checksum, this comparison cannot establish trust. If values differ, check the file version and ask for another copy.
Keep the record with the file
Download the .sha256 text file to retain the checksum and original filename. This tool accepts the digest alone for comparison, not an uploaded manifest. All file reads happen in 1 MiB chunks in a local worker, with actual byte progress and a cancel action.
About this tool
Are my file contents uploaded?
No. The file is read and hashed on your device in a worker. The website still loads code, fonts and its normal website measurement; file contents and checksum values are not sent for processing.
Why can two files with the same name have different checksums?
The checksum depends on file bytes, not the name. A changed document, metadata edit or recompressed image changes the bytes. Compare the same version before assuming a transfer problem.
Does a matching checksum mean a file is safe?
No. It is an integrity comparison, not a malware scan or proof of who published the file. Obtain the expected value through a trusted channel.
Which files and sizes can I check?
Any file type, including empty files, up to 2 GiB. Only one file is checked at a time. A 1 MiB read buffer keeps file processing bounded, but large files still take time and require the page to remain open.